Traveling vehicle

ABSTRACT

A traveling vehicle including a traveling machine body supported by a pair of left and right driving wheels; a pair of left motor and the right motor configured to independently drive the driving wheels; a riding part disposed behind the traveling machine body and connected to the traveling machine body, and configured to enable riding of a worker; a handle connected to the traveling machine body so as to be swingable left and right with respect to the traveling machine body; a plurality of load sensors for detecting a forward and backward weight shift of the worker who is riding on the riding part; a rotation angle sensor for detecting a leftward and rightward swinging operation amount of the handle; and a controller for controlling operation of the left and right motors based on detection values by the plurality of load sensors and the rotation angle sensor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/483,438, filed Sep. 11, 2014, to which benefit is claimed under 35USC § 120, and which claims priority under 35 USC § 119 of the followingthree applications: Japanese Patent Application 2013-267196, filed Dec.25, 2013; Japanese Patent Application 2013-267197, filed Dec. 25, 2013;and Japanese Patent Application 2013267198, filed Dec. 25, 2013. Thedisclosure of each of the aforementioned applications is herebyincorporated by reference thereto in its entirety.

BACKGROUND

1. Field of the Invention

The disclosure relates to a technology of a traveling vehicle thatindependently drives a pair of left and right driving wheels.

2. Description of Background

Heretofore, there is publicly known a technology of a traveling vehiclethat independently drives a pair of left and right driving wheels, forexample, as disclosed in U.S. Pat. No. 8,240,414.

U.S. Pat. No. 8,240,414 discloses a traveling vehicle that includes atraveling machine body which is supported by a pair of left and rightdriving wheels, and a pair of left and right motors which independentlydrives the pair of left and right driving wheels, respectively.

Further, there is publicly known a technology for operating a travelingvehicle, as disclosed in U.S. Pat. No. 8,262,104. U.S. Pat. No.8,262,104 discloses a traveling vehicle that includes a pair of left andright control levers. The pair of left and right driving wheels can bedriven independently by operating the pair of left and right controllevers, respectively. In such a traveling vehicle, the pair of left andright control levers is rotated in a front and back direction, so thatthe traveling vehicle can be made to travel in an arbitrary direction.

Specifically, the pair of left and right control levers is rotated bythe same amount, so that the traveling vehicle can be made to travelstraight. Additionally, the pair of left and right control levers isrotated by respective different amounts, so that the traveling vehiclecan be steered either right or left. The steering angle at this time isdetermined based on a difference between the rotation amounts of thepair of left and right control levers.

However the steering angle of the traveling vehicle is determined basedon the difference between the rotation amounts of the left and rightcontrol levers, and therefore such a traveling vehicle has room forimprovement in operability in respect that a worker needs to get used tosteering the traveling vehicle in a desired direction.

SUMMARY

In view of the above circumstances, an object of the disclosure providesa traveling vehicle for independently driving a pair of left and rightdriving wheels, which is excellent in operability.

The problem to be solved by the disclosure has been described above, andmeans for solving the problem is now described.

That is, a traveling vehicle according to the disclosure includes: atraveling machine body supported by a pair of left and right drivingwheels; a pair of left and right motors connected to the pair of leftand right driving wheels, respectively, and configured to independentlydrive the pair of left and right driving wheels, respectively; a ridingpart disposed behind the traveling machine body, connected to thetraveling machine body, and configured to enable riding of a worker; ahandle connected to the traveling machine body so as to be swingableleft and right with respect to the traveling machine body; a weightshift detection sensor configured to detect a forward and backwardweight shift of the worker who is riding on the riding part; a swingingoperation detection sensor configured to detect a leftward and rightwardswinging operation amount of the handle; and a controller configured tocontrol operation of the pair of left and right motors based ondetection values by the weight shift detection sensor and the swingingoperation detection sensor.

A traveling vehicle according to the disclosure includes: a travelingmachine body supported by a pair of left and right driving wheels; apair of left and right motors connected to the pair of left and rightdriving wheels, respectively, and configured to independently drive thepair of left and right driving wheels, respectively; a riding partdisposed behind the traveling machine body, connected to the travelingmachine body, configured to enable riding of a worker, and including aleg placing surface on which the worker places his/her leg when riding;a handle formed with a grip part configured to enable gripping of theworker who is riding on the riding part, connected to the travelingmachine body so as to be swingable left and right with respect to thetraveling machine body, and provided at such a position that a height ofa swing fulcrum is at most a half of a height from the leg placingsurface to the grip part, and is higher than a height of the leg placingsurface; a swinging operation detection sensor configured to detect aleftward and rightward swinging operation amount of the handle; and acontroller configured to control operation of the pair of left and rightmotors based on a detection value by the swinging operation detectionsensor.

A traveling vehicle according to the disclosure includes: a travelingmachine body supported by a pair of left and right driving wheels; apair of left and right motors connected to the pair of left and rightdriving wheels, respectively, and configured to independently drive thepair of left and right driving wheels, respectively; a work devicedisposed in front of the traveling machine body, and connected to thetraveling machine body; a riding part disposed behind the travelingmachine body, connected to the traveling machine body, and configured toenable riding of a worker; a weight shift detection sensor configured todetect a weight shift of the worker who is riding on the riding part;and a controller configured to control operation of the pair of left andright motors based on a detection value by the weight shift detectionsensor.

A traveling vehicle according to the disclosure includes: a travelingmachine body supported by a pair of left and right driving wheels; amotive power part for generating power for driving the pair of left andright driving wheels and transmitting the power to the pair of left andright driving wheels, the motive power part being provided in thetraveling machine body, a riding part disposed behind the travelingmachine body, connected to the traveling machine body, and configured toenable riding of a worker, a handle connected to the traveling machinebody, and provided so as to extend upward from the traveling machinebody; a driven wheel disposed at a position different from a rotationalaxis of the pair of left and right driving wheels; and a work devicedisposed in front of the traveling machine body, and connected to thetraveling machine body.

As effects of the disclosure, the following effects are obtained.

In the traveling vehicle according to the disclosure, it is possible toprovide a traveling vehicle for independently driving a pair of left andright driving wheels, which is excellent in operability. That is, theworker can shift the weight forward and backward while riding on theriding part, and perform the swinging operation of the handle to theleft and right, so that the worker can intuitively drive the travelingvehicle.

In the traveling vehicle according to the disclosure, it is possible toprovide a traveling vehicle for independently driving a pair of left andright driving wheels, which is excellent in operability. That is, it ispossible to reduce a difference between an inclination angle of thehandle to the left and right and an inclination angle of the posture ofthe worker to the left and right when the handle is swingably operated.Consequently, the worker can operate the handle without uncomfortablefeeling. Additionally, the swing fulcrum of the handle is provided at aposition higher than at least the leg placing surface of the ridingpart, and therefore it is possible to secure a space for disposing othermembers below the swing fulcrum.

In the traveling vehicle according to the disclosure, it is possible toprovide a traveling vehicle for independently driving a pair of left andright driving wheels, which is excellent in operability. That is, theworker can intuitively drive the traveling vehicle by shifting theweight while riding on the riding part.

In the traveling vehicle according to the disclosure, it is possible toprovide a traveling vehicle for independently driving a pair of left andright driving wheels, which is excellent in operability. That is, theworker can drive the traveling vehicle while visually recognizing thetraveling machine body and the work device located on the front at astate of riding on the riding part, and therefore it is possible toeasily operate the traveling vehicle.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view showing a situation where a worker rides on atraveling vehicle according to a first embodiment of the disclosure;

FIG. 2 is a side view of the traveling vehicle of this embodiment;

FIG. 3 is a rear view of the traveling vehicle;

FIG. 4 is a back perspective view of the traveling vehicle;

FIG. 5 is a plan view of the traveling vehicle;

FIG. 6 is a side view showing a traveling machine body and a ridingpart;

FIG. 7 is a rear view showing the traveling machine body and the ridingpar.

FIG. 8 is an exploded perspective view showing a machine body frame andthe riding part;

FIG. 9 is an exploded perspective view showing the riding part;

FIG. 10 is a plan view showing the riding part;

FIG. 11 is a side view showing a connecting part between a handle andthe traveling machine body;

FIG. 12 is a rear view showing the connecting part;

FIG. 13 is a schematic diagram showing a configuration related to thecontrol of the traveling vehicle;

FIG. 14 is a rear view showing a state where the worker swings thehandle left;

FIG. 15A is a schematic side view showing a riding part according to asecond embodiment, and FIG. 15B is a schematic side view showing ariding part according to a third embodiment;

FIG. 16A is a schematic side view showing a riding part according to afifth embodiment;

FIG. 16B is a schematic rear view showing the riding part;

FIG. 17 is a schematic side view showing a riding part according to asixth embodiment;

FIG. 18 is a schematic diagram showing a configuration related to thecontrol of a traveling vehicle according to a seventh embodiment;

FIG. 19 is a side view showing a traveling machine body and a ridingpart of the traveling vehicle according to the seventh embodiment;

FIG. 20 is a schematic diagram showing a configuration related to thecontrol of a traveling vehicle according to an eighth embodiment;

FIG. 21 is a side view showing a traveling machine body and a ridingpart of the traveling vehicle according to the eighth embodiment; and

FIG. 22 is a side view showing a traveling vehicle according to a ninthembodiment.

DETAILED DESCRIPTION

Hereinafter the direction of an arrow U, the direction of an arrow D,the direction of an arrow L, the direction of an arrow R, the directionof an arrow F, and the direction of an arrow B shown in the drawings aredefined as an upper direction, a lower direction, a left direction, aright direction, a front direction, and a back direction, respectively,and description is made.

Hereinafter an entire configuration of a traveling vehicle 1 accordingto an embodiment (a first embodiment) of the disclosure is describedwith reference to FIGS. 1 to 5.

The traveling vehicle 1, on which a worker rides, travels, and enablesthe worker to perform predetermined work. The traveling vehicle 1 mainlyincludes a traveling machine body 10, a motive power part 20, a drivingwheel 30L and a driving wheel 30R, a riding part 40, a driven wheel 60Land a driven wheel 60R, a handle 70, and a mower unit 90.

The traveling machine body 10 is supported by a pair of the left andright driving wheels 30L and 30R. The traveling machine body 10 isprovided with the motive power part 20 for driving the pair of left andright driving wheels 30L and 30R. To the back part of the travelingmachine body 10, the riding part 40 on which the worker rides isconnected. In both left and right ends of the riding part 40, the drivenwheel 60L and the driven wheel 60R are provided respectively. To theupper part of the traveling machine body 10, the handle 70 is connected,and is provided so as to extend upward. To the front part of thetraveling machine body 10, the mower unit 90 that is a work device forlawn mowing is connected.

In the traveling vehicle 1 thus configured, the worker rides on theriding part 40 to grip the handle 70 by a hand, so that the worker canstably ride on the traveling vehicle 1. Additionally, the workerperforms predetermined operation, so that the worker can independentlydrive the pair of left and right driving wheels 30L and 30R to enablethe traveling vehicle 1 to travel arbitrarily. That is, whilearbitrarily steering the traveling vehicle 1 left and right, the workercan move the traveling vehicle 1 forward or backward, and turn thetraveling vehicle 1 on the spot. Furthermore, the worker performspredetermined operation, so that the worker drives the mower unit 90 toenable lawn mowing work.

Hereinafter a configuration of each part of the traveling vehicle 1 isdescribed.

The traveling machine body 10 shown in FIG. 1, FIG. 2, FIG. 4 to FIG. 8,FIG. 11, and FIG. 12 mainly includes a machine body frame 11, and amachine body cover 12.

The machine body frame 11 shown in FIG. 4 to FIG. 8 serves as a mainstructure of the traveling machine body 10. The machine body frame 11mainly includes a lower frame 11 a, side frames 11 b, vertical frames 11c, an upper frame 11 d, a front frame 11 e, a handle supporting part 11f, and a spring supporting plate 11 g. The lower frame 11 a, the sideframes 11 b, and the upper frame 11 d each are formed by properlybending a cylindrical member.

The lower frame 11 a forms a bottom of the machine body frame 11. Thelower frame 11 a is formed in a substantially rectangular shape in planview. Inside the lower frame 11 a, a flat plate 11 j is fixed. The flatplate 11 j forms a bottom surface of the machine body frame 11. In rearends of the lower frame 11 a, connection brackets 11 h for connectingthe riding part 40 described later are provided.

The side frames 11 b form both left and right parts of the machine bodyframe 11. The side frames 11 b are formed in an inverted U-shape in sideview. The respective side frames 11 b are disposed on left and rightsides of the machine body frame 11, and fixed to both left and rightends of the lower frame 11 a.

The two vertical frames 11 c are disposed on each of the left and rightsides of the machine body frame 11, and are fixed to the side frames 11b and the lower frame 11 a so as to connect upper ends of the sideframes 11 b and side parts of the lower frame 11 a.

The upper frame 11 d connects the left and right side frames 11 b. Theupper frame 11 d is formed in an inverted U-shape in rear view (in frontview). Both left and right ends of the upper frame 11 d are fixed to therespective upper parts of the left and right side frames 11 b.

The front frame 11 e forms the front part of the machine body frame 11.The front frame 11 e has a first end connected to a central part in theleft and right direction of the upper frame 11 d. The front frame 11 ehas a second end that extends downward in the front direction.

The handle supporting part 11 f shown in FIG. 11 and FIG. 12 is a partfor supporting the handle 70 described later. The handle supporting part11 f is fixed to the lower part of the central part in the left andright direction of the upper frame 11 d. The handle supporting part 11 fis formed with a through hole in a front and back direction.

The spring supporting plate 11 g is a rectangular plate-shaped member.The spring supporting plate 11 g is fixed to the upper frame 11 d so asto extend backward from the central part in the left and right directionof the upper frame 11 d.

A space surrounded by the machine body frame 11 thus configured is ahousing space S for housing component members of the motive power part20 described later.

The machine body cover 12 shown in FIG. 1 and FIG. 2 is fixed to themachine body frame 11 so as to cover the housing space S of the machinebody frame 11. The machine body cover 12 can conceals the machine bodyframe 11 and a device provided in the machine body frame 11 (motivepower part 20 described below).

The motive power part 20 shown in FIG. 4, FIG. 6, and FIG. 7 generatespower for driving the driving wheel 30L and the driving wheel 30R, andtransmits the power to the driving wheel 30L and the driving wheel 30R.The motive power part 20 mainly includes a battery 21, a left motor 22Land a right motor 22R, a left power transmission mechanism 23L and aright power transmission mechanism 23R, and a controller box 24.

The battery 21 stores electric power for driving the traveling vehicle1. The battery 21 is fixed onto the lower frame 11 a of the machine bodyframe 11. The battery 21 is disposed in the lower part of the housingspace S so as to range from the front end to the rear end of the housingspace S.

The left motor 22L and the right motor 22R are an embodiment of a motoraccording to the disclosure, and are power sources for independentlydriving the pair of left and right driving wheels 30L and 30R,respectively. The left motor 22L and the right motor 22R can generaterotational power by using supplied electric power. The left motor 22Land the right motor 22R are disposed side by side on the left and rightinside the housing space S, respectively. The left motor 22L and theright motor 22R are disposed on a substantially central part in a frontand back direction of the housing space S right above the battery 21.

The left power transmission mechanism 23L and the right powertransmission mechanism 23R are an embodiment of a power transmissionmechanism according to the disclosure, and properly decelerate powerfrom the left motor 22L and the right motor 22R, and thereafter transmitthe decelerated power to the pair of left and right driving wheels 30Land 30R. The left power transmission mechanism 23L is connected to theleft motor 22L to be fixed to the left side surface (vertical frame 11c) of the machine body frame 11. The right power transmission mechanism23R is connected to the right motor 22R to be fixed to the right sidesurface (vertical frames 11 c) of the machine body frame 11. The leftpower transmission mechanism 23L has an axle (output shaft) that isconnected to the driving wheel 301, and the right power transmissionmechanism 23R has an axle that is connected to the driving wheel 30R.The axle of the left power transmission mechanism 23L and the axle ofthe right power transmission mechanism 23R are disposed on the sameaxis, and therefore the pair of left and right driving wheels 30L and30R are disposed on the same axis.

The controller box 24 houses devices for controlling the driving of thetraveling vehicle 1 (e.g., a controller 24 a, a left inverter 24 b, aright inverter 24 c, a working inverter 24 d, and the like which aredescribed later). The controller box 24 is disposed in the upper part ofthe housing space S so as to range from the front to the back of theleft motor 22L and the right motor 22R through the upper parts.

The controller 24 a and the like housed in the controller box 24 aredescribed later.

The driving wheel 30L and the driving wheel 30R support the travelingmachine body 10, and rotate to allow to the traveling machine body 10 totravel. The driving wheel 30L and the driving wheel 30R support thetraveling machine body 10 through the motive power part 20 (the leftpower transmission mechanism 23L and the right power transmissionmechanism 23R).

Herein, in side view (see FIG. 6), a part of the component members ofthe motive power part 20 is disposed at such a position as to overlapwith the driving wheel 30L and the driving wheel 30R. Specially, theleft motor 221, the right motor 22R, the left power transmissionmechanism 23L, and the right power transmission mechanism 23R aredisposed at such a position that the whole of the left motor 22L, theright motor 22R, the left power transmission mechanism 231, and theright power transmission mechanism 23R overlaps with the driving wheel30L and the driving wheel 30R. Thus, the component members of the motivepower part 20 are disposed so as to overlap with the driving wheel 30Land the driving wheel 30R in side view, so that the traveling vehicle 1can be made compact.

The riding part 40 shown in FIG. 7 to FIG. 10 is disposed behind thetraveling machine body 10, is connected to the traveling machine body10, and is configured to enable the riding of the worker. The ridingpart 40 mainly includes a first member 41 and a second member 43.

The first member 41 is a plate-shaped member. The first member 41 mainlyincludes a central part 41 a, a left part 41 b, and a right part 41 c.

The central part 41 a is a part formed in a rectangle in plan view. Theleft part 41 b and the right part 41 c are part formed by bending theleft end and the right end of the first member 41 such that the left endand the right end rise.

On the bottom surface of the first member 41, a cylindrical connectingpart 41 d, the longitudinal direction of which is directed in thesubstantially front and back direction, is provided. A swinging shaft 42is rotatably inserted into the connection brackets 11 h of the machinebody frame 11, and the connecting part 41 d, so that the first member 41is connected to the connection brackets 11 h. The swinging shaft 42 isdisposed such that the longitudinal direction of the swinging shaft 42is directed in the substantially front and back direction. The firstmember 41 can swing to the left and right with respect to the travelingmachine body 10 around the swinging shaft 42.

The second member 43 is a plate-shaped member. The second member 43 isformed in a rectangle that is one size smaller than the central part 41a of the first member 41, in plan view. In a central part in a left andright direction of the second member 43, a partition part 43 a isformed. The partition part 43 a is a part formed such that the centralpart in the left and right direction of the second member 43 rises fromthe front to the back. In the front end of the partition part 43 a, anopening 43 b that communicates the inside and the outside of thepartition part 43 a is formed. The partition part 43 a partitions anupper surface of the second member 43 into the left and right. Thesurface on the left of the thus partitioned upper surface of the secondmember 43 serves as a left leg placing surface 44L for placing a leftleg of the worker. Similarly, the surface on the right of the uppersurface of the second member 43 serves as a right leg placing surface44R for placing a right leg of the worker. The partition part 43 a isformed in the second member 43, so that a part where the left leg of theworker is placed, and a part where the right leg is placed can beapparently distinguished. The second member 43 is disposed on the upperpart of the central part 41 a of the first member 41.

Between the first member 41 and the second member 43, a plurality ofload sensors (a left front load sensor 50 a, a left back load sensor 50b, a right front load sensor 50 c, and a right back load sensor 50 d)are disposed. The plurality of load sensors are an embodiment of aweight shift detection sensor according to the disclosure. Specifically,the second member 43 is placed an the plurality of load sensors disposedon the upper surface of the first member 41. The plurality of loadsensors can detect a load applied to the second member 43 (specifically,a load by the worker who is riding an the second member 43).

The left front load sensor 50 a is disposed near the front end of theleft leg placing surface 44L of the second member 43 in plan view.

The left back load sensor 50 b is disposed behind the left front loadsensor 50 a and near the rear end of the left leg placing surface 44L ofthe second member 43 in plan view.

The right front load sensor 50 c is disposed near the front end of theright leg placing surface 44R of the second member 43 (at a positionsymmetrical to the left front load sensor 50 a with the partition part43 a interposed between the right front load sensor 50 c and the leftfront load sensor 50 a) in plan view.

The right back load sensor 50 d is disposed near the rear end of theright leg placing surface 44R of the second member 43 (at a positionsymmetrical to the left back load sensor 50 b with the partition part 43a interposed between the right back load sensor 50 d and the left backload sensor 50 b) in plan view.

Thus, the left front load sensor 50 a and the right front load sensor 50c, and the left back load sensor 50 b and the right back load sensor 50d are disposed by being shifted in the front and back direction.Additionally, the left front load sensor 50 a and the left back loadsensor 50 b, and the right front load sensor 50 c and the right backload sensor 50 d are disposed by being shifted in the left and rightdirection.

Wires 51 connected to the left front load sensor 50 a, the left backload sensor 50 b, the right front load sensor 50 c, and the right backload sensor 50 d are collected to the center in the left and rightdirection, and are guided forward through a space inside the partitionpart 43 a of the second member 43. The wires 51 are guided to theoutside of the partition part 43 a through the opening 43 b, to beconnected to the controller 24 a described later.

The driven wheel 60L and the driven wheel 60R support the riding part.The driven wheel 60L and the driven wheel 60R are provided below theleft part 41 b and the right part 41 c of the first member 41,respectively. The driven wheel 60L and the driven wheel 60R arenon-driving wheels, and can rotate while freely changing the directionin accordance with the movement of the traveling vehicle 1.

The handle 70 shown in FIG. 2 to FIG. 4, FIG. 11, and FIG. 12 is anembodiment of a handle and a holding part according to the disclosure,and is connected to the traveling machine body 10 so as to be swingableleft and right with respect to the traveling machine body 10. The handle70 mainly includes a fulcrum shaft 71, a handle main body 72, a grippart 73, and a work switch 74.

The fulcrum shaft 71 shown in FIG. 11 and FIG. 12 serves as a swingfulcrum of the handle 70. The fulcrum shaft 71 is rotatably insertedinto the through hole of the handle supporting part 11 f of the machinebody frame 11 with the longitudinal direction of the fulcrum shaft 71being directed in the front and back direction.

The handle main body 72 shown in FIG. 2 to FIG. 4 is a main structure ofthe handle 70. The handle main body 72 is provided so as to extendupward from the rear upper part of the traveling machine body 10.

As shown in FIG. 11 and FIG. 12, a part near the lower end of the handlemain body 72 is branched into the left and right, and the branched partsare fixed to the rear end of the fulcrum shaft 71 through a pair of leftand right spacers 72 a. Consequently, the handle main body 72 isconnected to the traveling machine body 10 so as to be swingable leftand right with respect to the traveling machine body 10.

In the part near the lower end of the handle main body 72 (above thefulcrum shaft 71), a pair of a left spring supporting plate 75L and aright spring supporting plate 75R is provided. The left springsupporting plate 75L and the right spring supporting plate 75R aredisposed with the rear end of the spring supporting plate 11 g of themachine body frame 11 between the left spring supporting plate 75L andthe right spring supporting plate 75R. Between the left springsupporting plate 75L and the spring supporting plate 11 g, a left spring76L that is a compression coil spring is disposed. Between the rightspring supporting plate 75R and the spring supporting plate 11 g, aright spring 76R that is a compression coil spring is disposed. Springconstants of the left spring 76L and the right spring 76R are preset tothe same value. The left spring 76L and the right spring 76R equallyurge the handle main body 72 left and right, so that the handle mainbody 72 is held in an upright state.

The grip part 73 shown in FIG. 2 to FIG. 4 is a part where the workerwho is riding on the riding part 40 can grip. The grip part 73 is formedso as to extend from the upper end of the handle main body 72 to theleft and right. The height of the grip part 73 (i.e., the height of theupper end of the handle main body 72) is preset to a height allowingeasy gripping of the worker who is riding on the riding part 40 (e.g., aheight equal to the level of a chest of the worker (see FIG. 1)).

The work switch 74 is an operation tool for switching on and off of theoperation of the mower unit 90 described later. The work switch 74 isprovided in the middle in the vertical direction of the handle main body72.

In the handle 70 thus configured, the worker can swingably operate thehandle 70 (handle main body 72) left and right with the fulcrum shaft 71as a swing fulcrum. At this time, the handle main body 72 is urged bythe left spring 76L and the right spring 76R so as to return to theupright state (see FIG. 12). The larger the swinging operation amount ofthe handle main body 72 is, the larger the urging force is.Consequently, the worker can easily return the swung handle main body 72to the upright state, and the operability of the handle 70 can beimproved.

The fulcrum shaft 71 of the handle 70 is located above the motive powerpart 20 (the housing space S of the traveling machine body 10). That is,as shown in FIG. 2, the fulcrum shaft 71 is provided at such a positionas to be higher than the leg placing surfaces (the left leg placingsurface 44L and the right leg placing surface 44R) of the riding part40. Specifically, the fulcrum shaft 71 is provided at a position of aheight h from the leg placing surfaces of the riding part 40. Themounting position of the fulcrum shaft 71 is set such that this height his at most a half of a height H from the leg placing surfaces of theriding part 40 to the grip part 73. Particularly, in this embodiment,the height h is set to at least one-third of the height H. That is, inthis embodiment, a relation of H/3≤h≤H/2 is established.

As shown in FIG. 11, to the front end of the fulcrum shaft 71, arotation angle sensor 80 is connected. The rotation angle sensor 80 isan embodiment of a swinging operation detection sensor according to thedisclosure. The rotation angle sensor 80 is configured by apotentiometer. The rotation angle sensor 80 is fixed to a part near theupper end of the front frame 11 e, and is connected to the front end ofthe fulcrum shaft 71. Consequently, the rotation angle sensor 80 candetect the rotation angle of the fulcrum shaft 71, and also detect theswinging operation amount of the handle 70.

The mower unit 90 shown in FIG. 2, FIG. 4 and FIG. 5 is an embodiment ofa work device according to the disclosure, and is a work device forperforming lawn mowing work. The mower unit 90 is disposed in front ofthe traveling machine body 10, and connected to the traveling machinebody 10. The mower unit 90 mainly includes blades 91, blade motors 92, agauge wheel 93, and a lifting and lowering link 94.

The mower unit 90 is provided with the two blades 91 rotatably. To therespective blades, the blade motors 92 for driving the blades 91 areconnected. In the front end of the mower unit 90, the gauge wheel 93capable of rotating while freely changing the direction in accordancewith the movement of the traveling vehicle 1 is provided. The mower unit90 is liftably connected to the traveling machine body 10 through thelifting and lowering link 94.

Hereinafter a configuration for controlling the driving of the travelingvehicle 1 is described with reference to FIG. 13.

The controller 24 a controls the operation of each connected device. Thecontroller 24 a is configured by a storage part, an arithmeticprocessing part, and the like. The controller 24 a stores a program forcontrolling each device and various data.

The controller 24 a is connected to the left front load sensor 50 a, theleft back load sensor 50 b, the right front load sensor 50 c, and theright back load sensor 50 d, and can receive results of loads detectedby these load sensors.

The controller 24 a is connected to the rotation angle sensor 80, andcan receive a result of the swinging operation amount of the handle 70detected by the rotation angle sensor 80.

The controller 24 a is connected to the work switch 74, and can receivea signal related to the operation of the work switch 74.

The controller 24 a is connected to the left inverter 24 b, and cancontrol the operation of the left inverter 24 b. The controller 24 aoptionally supplies electric power from battery 21 to the left motor 22Lthrough the left inverter 24 b, so that the rotational speed of thedriving wheel 30L can be optionally controlled.

The controller 24 a is connected to the right inverter 24 c, and cancontrol the driving of the right inverter 24 c. The controller 24 aoptionally supplies electric power from battery 21 to the right motor22R through the right inverter 24 c, so that the rotational speed of thedriving wheel 30R can be optionally controlled.

The controller 24 a is connected to the working inverter 24 d, and cancontrol the driving of the working inverter 24 d. The controller 24 aoptionally supplies electric power from battery 21 to the blade motors92 through the working inverter 24 d, so that the blades 91 can berotated to perform lawn mowing work.

Hereinafter control performed by the controller 24 a when a workerdrives the traveling vehicle 1 configured as described above isdescribed.

In a case where the traveling vehicle 1 is driven, the worker rides onthe riding part 40, and grips the grip part 73 of the handle 70 by ahand (see FIG. 1). At this time, a left leg and a right leg of theworker are placed on the left leg placing surface 44L and the right legplacing surface 44R, respectively (see FIG. 10).

When the worker shifts his/her weight forward and backward(specifically, applies his/her weight to toes or heels), the controller24 a moves the traveling vehicle 1 forward or backward based on theforward and backward weight shift of the worker. Hereinafter, specificdescription is made.

The controller 24 a calculates a forward and backward weight shift ofthe worker based on loads always detected by the plurality of loadsensors (the left front load sensor 50 a, the left back load sensor 50b, the right front load sensor 50 c, and the right back load sensor 50d). Specifically, the controller 24 a calculates a weight shift of theworker from change of balance between a total value of loads detected bythe left front load sensor 50 a and the right front load sensor 50 c,and a total value of loads detected by the left back load sensor 50 b,and the right back load sensor 50 d.

The detection values of the plurality of load sensors that are used as areference of the calculation of the weight shift (detection valuesdetected when the traveling vehicle does not move forward and backward)can be set by an arbitrary method. For example, the controller 24 a canbe configured to previously store the detection values, or storedetection values of the plurality of load sensors detected when theworker rides on the riding part 40.

When determining that the weight shift of the worker occurs, thecontroller 24 a supplies electric power to the left motor 22L and theright motor 22R to drive the driving wheel 30L and the driving wheel30R. Specifically, in a case where a forward weight shift occurs, thecontroller 24 a rotates the driving wheel 30L and the driving wheel 30Rforward to move the traveling vehicle 1 forward. In a case where abackward weight shift occurs, the controller 24 a rotates the drivingwheel 30L and the driving wheel 30R backward to move the travelingvehicle 1 backward. Additionally, the controller 24 a increases therotational speeds of the driving wheel 30L and the driving wheel 30R asthe weight shift amount of the worker is larger, and moves the travelingvehicle 1 forward or backward at a higher speed.

When the worker swings the handle 70 left and right, the controller 24 aturns the traveling vehicle 1 left or right based on the swingingoperation amount of the handle 70. Hereinafter, specific description ismade.

The controller 24 a supplies electric power to the left motor 22L andthe right motor 22R based on the swinging operation amount of the handle70 always detected by the rotation angle sensor 80, to drive the drivingwheel 30L and the driving wheel 30R. Specifically, when the handle 70 isswingably operated left (see FIG. 14), the controller 24 a rotates thedriving wheel 30L backward, and rotates the driving wheel 30R forward,to turn the traveling vehicle 1 in the left direction an the spot.Additionally, when the handle 70 is swingably operated right, thecontroller 24 a rotates the driving wheel 30L forward, and rotates thedriving wheel 30R backward, to turn the traveling vehicle 1 in the rightdirection on the spot.

Furthermore, when the weight shift of the worker and the swingingoperation of the handle 70 are performed at the same time, thecontroller 24 a can turn the traveling vehicle 1 left or right whilemoving the traveling vehicle 1 forward or backward (i.e., turn to theleft or the right). Thus, the worker performs the weight shift and theswinging operation of the handle 70, so that the worker can intuitivelydrive the traveling vehicle 1.

When the worker operates the work switch 74 (ON operation), thecontroller 24 a supplies electric power to the blade motors 92 to rotatethe blades 91. The traveling vehicle 1 is allowed to travel in thisstate, so that lawn mowing work can be performed. Furthermore, when theworker operates the work switch 74 (OFF operation), the controller 24 astops supplying electric power to the blade motors 92, to stop rotatingthe blades 91.

Hereinafter, a relation between an inclination of the handle 70 andposture of the worker when the handle 70 is swingably operated isdescribed.

As shown in FIG. 14, the height h of the fulcrum shaft 71, which servesas the swing fulcrum of the handle 70, from the leg placing surfaces isset to a height ranging from at most a half of the height H of the grippart 73 from the leg placing surfaces to at least one-third of theheight H.

Thus, the swing fulcrum of the handle 70 is disposed at a position aslow as possible, so that a difference between an inclination angle ofthe handle 70 to the left and right and an inclination angle of theposture of the worker to the left and right when the handle 70 isswingably operated can be reduced. Consequently, it is possible toeliminate uncomfortable feeling when the handle 70 is operated, and toimprove the operability of the handle 70.

Furthermore, the height h from the leg placing surfaces to the swingfulcrum of the handle 70 is secured to the minimum (at least H/3), sothat a space for disposing other devices can be secured below the handle70. In this embodiment, the motive power part 20 is disposed below thehandle 70, so that the traveling vehicle 1 can be made compact.

Hereinafter a second embodiment of the traveling vehicle according tothe disclosure is described.

Although the riding part 40 according to the first embodiment isconfigured to detect a weight shift of a worker by using the pluralityof load sensors, the riding part can be configured to detect the weightshift of a worker by using a rotation angle sensor 52.

Specifically, as shown in FIG. 15A, a second member 43 is rotatablyconnected to an upper part of a first member 41 through a rotation shaft45. The rotation shaft 45 is disposed in a central part in a front andback direction of the second member 43 with a longitudinal direction ofthe rotation shaft 45 being directed to a left and right direction. Therotation shaft 45 is fixed to the second member 43 to be integrallyrotatable with the second member 43. The second member 43 can rotate(swing) forward and backward by the weight shift of a worker who isriding on the second member 43. Below both front and rear ends of thesecond member 43, respective springs 46 are disposed. The springs 46urge the second member 43 such that the second member 43 returns to aposition parallel to the first member 41. The rotation shaft 45 isprovided with the rotation angle sensor 52. The rotation angle sensor 52can detect the rotation angle of the rotation shaft 45, and can alsodetect a swing angle of the second member 43 with respect to the firstmember 41.

A controller 24 a can calculate the weight shift of the worker from theswing angle of the second member 43 detected by the rotation anglesensor 52. The controller 24 a can drive a driving wheel 30L and adriving wheel 30R based on the calculated weight shift of the worker tomove the traveling vehicle 1 forward or backward.

Hereinafter a third embodiment of the traveling vehicle according to thedisclosure is described.

Although the riding part 40 according to the second embodiment isconfigured to detect the weight shift of a worker by using the rotationangle sensor 5Z the riding part can be configured to detect the weightshift of a worker by using limit switches 53.

Specifically, as shown in FIG. 15B, in a front end and a rear end of anupper surface of a first member 41, the contact type limit switches 53are disposed. When a second member 43 swings forward and backward by apredetermined angle with respect to the first member 41, the front endor the rear end of the second member 43 comes into contact with thelimit switch 53. Consequently, it is possible to detect that the secondmember 43 swings forward or backward with respect to the first member41.

In a case where a controller 24 a detects that the second member 43swings forward, the controller 24 a rotates a driving wheel 30L and adriving wheel 30R forward to move a traveling vehicle 1 forward.Additionally, in a case where the controller 24 a detects that thesecond member 43 swings backward, the controller 24 a rotates thedriving wheel 30L and the driving wheel 30R backward to move thetraveling vehicle 1 backward.

Although the contact type limit switches 53 are used in the thirdembodiment, another sensor (a contact type sensor or a noncontact typesensor) can be used.

Hereinafter, a fourth embodiment of the traveling vehicle according tothe disclosure is described.

Although the traveling vehicle 1 according to the first embodiment isconfigured to turn left or right based on the swinging operation amountof the handle 70, the traveling vehicle 1 can be configured to turn leftor right based on the weight shift of a worker. Hereinafter, specificdescription is made with reference to FIG. 10.

A controller 24 a calculates a forward and backward weight shift and aleftward and rightward weight shift of a worker based on loads alwaysdetected by a plurality of load sensors. Specifically, the controller 24a calculates the forward and backward weight shift of the worker fromchange of balance between a total value of loads detected by the leftfront load sensor 50 a and the right front load sensor 50 c, and a totalvalue of loads detected by the left back load sensor 50 b and the rightback load sensor 50 d. Additionally, the controller 24 a calculates theleftward and rightward weight shift of the worker from change of balancebetween a total value of loads detected by the left front load sensor 50a and the left back load sensor 50 b, and a total value of loadsdetected by the right front load sensor 50 c and the right back loadsensor 50 d.

In a case where the controller 24 a determines that the forward andbackward weight shift occurs, the controller 24 a drives a driving wheel30L and a driving wheel 30R to move a traveling vehicle 1 forward orbackward. The controller 24 a moves the traveling vehicle 1 forward orbackward at a higher speed as the forward and backward weight shiftamount is larger.

In a case where the controller 24 a determines that the leftward andrightward weight shift occurs, the controller 24 a rotates the drivingwheel 30L and the driving wheel 30R in the opposite directions, to turnthe traveling vehicle 1 left or right. The controller 24 a turns thetraveling vehicle 1 left or right at a higher speed as the leftward andrightward weight shift amount is larger.

Furthermore, in a case where the forward and backward weight shift andthe leftward and rightward weight shift are performed at the same time,the controller 24 a can turn the traveling vehicle 1 left and rightwhile moving the traveling vehicle 1 forward or backward (i.e., turn tothe left or the right). Thus, the worker can intuitively drive thetraveling vehicle 1 only by weight shift.

In the traveling vehicle 1 according to the fourth embodiment, thedriving wheel 30L and the driving wheel 30R are not controlled based onthe swinging operation amount of a handle 70. Thus, the handle 70 may befixed to the traveling machine body 10 so as not to be swingable.

In the fourth embodiment, the traveling vehicle 1 is turned left orright only by the leftward and rightward weight shift of a worker.However, in addition to the above, the traveling vehicle 1 can beconfigured to be turned left or right based on the leftward andrightward swinging operation amount of the handle 70. For example, thetraveling vehicle 1 can be configured to be slowly turned, in a casewhere only a leftward and rightward weight shift is detected.Additionally, the traveling vehicle 1 can be configured to be quicklyturned, in a case where the swinging operation of the handle 70 isdetected in addition to the leftward and rightward weight shift.

Hereinafter a fifth embodiment of the traveling vehicle according to thedisclosure is described.

Although the riding part 40 according to the fourth embodiment isconfigured such that the weight shift of a worker is detected by usingthe plurality of load sensors, the riding part can be configured suchthat the weight shift of a worker is detected by using a first rotationangle sensor 54 a and a second rotation angle sensor 54 b.

Specifically, as shown in FIGS. 16A and 16B, a third member 47 isprovided above a second member 43 of a riding part 40. Between a firstmember 41 and the second member 43, a rotation shaft 48 a is provided.The second member 43 can swing forward and backward with respect to thefirst member 41 around the rotation shaft 48 a. The rotation shaft 48 ais provided with the first rotation angle sensor 54 a, and the swingangle of the second member 43 can be detected. Additionally, between thesecond member 43 and the third member 47, a rotation shaft 48 b isprovided. The third member 47 can swing to the left and right withrespect to the second member 43 around the rotation shaft 48 b. Therotation shaft 48 b is provided with the second rotation angle sensor 54b, and the swing angle of the third member 47 can be detected. Belowboth the front and rear ends of the second member 43 (between the secondmember 43 and the first member 41), respective springs 46 are disposed.The springs 46 urge the second member 43 such that the second member 43returns to a position parallel to the first member 41. Additionally,below both the left and right ends of the third member 47 (between thethird member 47 and the second member 43), respective springs 46 aredisposed. The springs 46 urge the third member 47 such that the thirdmember 47 returns to a position parallel to the second member 43.

In the riding part 40 thus configured, a worker rides on the thirdmember 47. A controller 24 a can calculate the forward and backwardweight shift of the worker from the swing angle of the second member 43detected by the first rotation angle sensor 54 a. Additionally, thecontroller 24 a can calculate the leftward and rightward weight shift ofthe worker from the swing angle of the third member 47 detected by thesecond rotation angle sensor 54 b.

Although the first rotation angle sensor 54 a and the second rotationangle sensor 54 b are used in the fifth embodiment, the forward andbackward weight shift and the leftward and rightward weight shift of theworker can be detected by using limit switches, similarly to a thirdembodiment.

Hereinafter, a sixth embodiment of the traveling vehicle according tothe disclosure is described.

In the riding part 40 according to the fifth embodiment, the member onwhich a worker rides (third member 47) is swingable forward andbackward, and to the left and right by using the rotation shafts (therotation shaft 48 a and the rotation shaft 48 b). However, a ball joint49 can be used.

Specifically, as shown in FIG. 17, below the central part of a secondmember 43 (between the second member 43 and a first member 41) the balljoint 49 is provided. A spherical part 49 a of the ball joint 49, and asaucer 49 b of the ball joint 49 are fixed to the second member 43 andthe first member 41, respectively. The spherical part 49 a is slidablysupported by the saucer 49 b, so that the second member 43 can swing inan arbitrary direction with respect to the first member 41. The secondmember 43 is provided with a gyro sensor 55, and the swing direction andthe swing angle of the second member 43 can be detected. Below both thefront and rear ends and both the left and right ends of the secondmember 43 (between second member 43 and the first member 41), respectivesprings 46 are disposed. The springs 46 urge the second member 43 suchthat the second member 43 returns to a position parallel to the firstmember 41.

In FIG. 17, the springs 46 disposed below both the left and right endsof the second member 43 are not shown. The number of the springs 46 isnot limited, and any number may be employed as long as the springs 46urge the second member 43 such that the second member 43 returns to theposition parallel to the first member.

In the riding part 40 thus configured, a worker rides on the secondmember 43. A controller 24 a can calculate the forward and backwardweight shift and the leftward and rightward weight shift of the workerfrom the swing direction and the swing angle of the second member 43detected by the gyro sensor 55.

Although the gyro sensor 55 is used in the sixth embodiment, the forwardand backward weight shift and the leftward and rightward weight shift ofthe worker can be detected by using limit switches, similarly to thethird embodiment.

Hereinafter, a seventh embodiment of the traveling vehicle according tothe disclosure is described.

Although the traveling vehicle 1 according to the first embodiment isconfigured to drive the driving wheel 30L and the driving wheel 30R byusing electric power stored in the battery 21, the traveling vehicle canbe configured to drive the driving wheel 30L and the driving wheel 30Rby using power of an engine 100.

Specifically, as shown in FIG. 18, in a traveling vehicle 1 according tothe seventh embodiment, a motive power part 20 includes the engine 100,a deceleration device 101, a left hydraulic pump 102L, a right hydraulicpump 102R, a left hydraulic motor 104L, a right hydraulic motor 104R,and a working clutch 105.

Power of the engine 100 is properly decelerated by the decelerationdevice 101, to be transmitted to the left hydraulic pump 102L and theright hydraulic pump 102R. The left hydraulic pump 102L and the righthydraulic pump 102R pump hydraulic oil by using the power from theengine 100. The hydraulic oil pumped from the left hydraulic pump 102Land the right hydraulic pump 102R is supplied to the left hydraulicmotor 104L and the right hydraulic motor 104R. The left hydraulic motor104L and the right hydraulic motor 104R are connected to a driving wheel30L and a driving wheel 30R, respectively, and the left hydraulic motor104L and the right hydraulic motor 104R can drive the driving wheel 30Land the driving wheel 30R, respectively. A controller 24 a controls theoperation of the left hydraulic pump 102L and the right hydraulic pump102R (more specifically, a discharge quantity of hydraulic oil), so thatit is possible to control hydraulic oil supplied to the left hydraulicmotor 104L and the right hydraulic motor 104R, and also possible tocontrol the rotation of the driving wheel 30L and the driving wheel 30R.The left hydraulic pump 102L and the left hydraulic motor 104L form aleft HST (hydrostatic continuously variable transmission) 106L.Additionally, the right hydraulic pump 102R and the right hydraulicmotor 104R form a right HST 106R.

The power of the engine 100 is transmitted to the working clutch 105through the deceleration device 101. At this time, the power transmittedfrom the engine 100 to the working clutch 105 may be decelerated or notdecelerate by the deceleration device 101. The power transmitted to theworking clutch 105 is transmitted to blades 91 of a mower unit 90through a belt for transmitting power. The operation of the workingclutch 105 is controlled by the controller 24 a. The working clutch 105is optionally turned on or turned off, so that the blades 91 can berotated or stopped.

As shown in FIG. 19, the motive power part 20 according to the seventhembodiment is also disposed in a housing space S of a machine body frame11, similarly to the first embodiment. Specifically, the engine 100 isdisposed in the back part of the housing space S, and the decelerationdevice 101 is disposed in a central part in a front and back directionof the housing space S. Additionally, the left HST 106L and the rightHST 106R are disposed above the deceleration device 101. A controllerbox 24 that houses the controller 24 a and the like is disposed in theupper part of the housing space S.

Also in the seventh embodiment, a part of the component members of themotive power part 20 is disposed at such a position as to overlap withthe driving wheel 30L and the driving wheel 30R in side view, similarlyto the first embodiment. Specifically, as shown in FIG. 19, thedeceleration device 101, the left HST 1061, and the right HST 106R aredisposed at such a position that the whole of the deceleration device101, the left HST 1061, and the right HST 106R overlaps with the drivingwheel 30L and the driving wheel 30R. Thus, the component members of themotive power part 20 are disposed so as to overlap with the drivingwheel 30L and the driving wheel 30R in side view, so that the travelingvehicle 1 can be made compact.

Hereinafter, an eighth embodiment of the traveling vehicle according tothe disclosure is described.

Although the traveling vehicle 1 according to the seventh embodiment isconfigured to pump hydraulic oil by using the left and right hydraulicpumps (the left hydraulic pump 102L and the right hydraulic pump 102R),the traveling vehicle can be configured to pump hydraulic oil by using asingle hydraulic pump 102.

Specifically, as shown in FIG. 20, in a traveling vehicle 1 according tothe eighth embodiment, a motive power part 20 includes an engine 100, adeceleration device 101, a hydraulic pump 102, a left regulating valve1031, a right regulating valve 103R, a left hydraulic motor 104L, aright hydraulic motor 104R, and a working clutch 105.

Power of the engine 100 is properly decelerated by the decelerationdevice 101, to be transmitted to the hydraulic pump 102. The hydraulicpump 102 pumps hydraulic oil by using the power from the engine 100. Thehydraulic oil pumped from the hydraulic pump 102 is supplied to the lefthydraulic motor 104L and the right hydraulic motor 104R through the leftregulating valve 103L and the right regulating valve 103R. The lefthydraulic motor 104L and the right hydraulic motor 104R are connected toa driving wheel 30L and a driving wheel 30R, respectively, and the lefthydraulic motor 104L and the right hydraulic motor 104R can drive thedriving wheel 30L and the driving wheel 30R, respectively. A controller24 a controls the operation of the left regulating valve 103L and theright regulating valve 103R, so that it is possible to control hydraulicoil supplied to the left hydraulic motor 104L and the right hydraulicmotor 104R, and also possible to control the rotation of the drivingwheel 30L and the driving wheel 30R.

As shown in FIG. 21, the motive power part 20 according to the eighthembodiment is also disposed in a housing space S of a machine body frame11, similarly to the first embodiment. Specifically, the engine 100 isdisposed in the back part of the housing space S, the decelerationdevice 101 is disposed in the central part in the front and backdirection of the housing space S, the hydraulic pump 102 is disposed inthe front part of the housing space S. Additionally, the left hydraulicmotor 104L and the right hydraulic motor 104R are disposed above thedeceleration device 101. A controller box 24 that houses the controller24 a and the like is disposed in the upper part of the housing space S.

Also in the eighth embodiment, a part of the component members of themotive power part 20 is disposed at such a position as to overlap withthe driving wheel 30L and the driving wheel 30R in side view, similarlyto the first embodiment. Specifically, as shown in FIG. 21, thedeceleration device 101, the hydraulic pump 102, the left hydraulicmotor 104L and the right hydraulic motor 104R are disposed at such aposition that the whole of the deceleration device 101, the hydraulicpump 102, the left hydraulic motor 104L and the right hydraulic motor104R overlaps with the driving wheel 30L and the driving wheel 30R.Thus, the component members of the motive power part 20 are disposed soas to overlap with the driving wheel 30L and the driving wheel 30R inside view, so that the traveling vehicle 1 can be made compact.

Hereinafter a ninth embodiment of the traveling vehicle according to thedisclosure is described.

In the ninth embodiment, as shown in FIG. 22, a riding part 40 and ahandle 70 are configured to be swingable forward and backward.Specifically, the front end of the riding part 40 is rotatably connectedto a traveling machine body 10. The rear end of the riding part 40 islifted, so that the riding part 40 can be swung forward to be folded.The riding part 40 is held by a holding mechanism (not shown) in a stateof swinging forward (in a state where the rear end is directed upward).

The handle 70 is provided with a swinging shaft in the middle in thevertical direction of a handle main body 72, and can swing a distal endside (grip part 73 side) forward and backward around the swinging shaft.The distal end side of the handle 70 can be held at an arbitraryposition by the holding mechanism (not shown).

With such a configuration, a worker can drive the traveling vehicle 1without riding on the riding part 40 while walking. At this time, thehandle 70 is swung forward and backward to a desired position, so thatthe handle 70 can be adjusted to an easily gripped position. In thiscase, the weight shift of the worker cannot be detected, and thereforethe handle 70 is provided with an operation tool (not shown) for drivingthe traveling vehicle 1.

In each of the above embodiments, the driven wheels (the driven wheel60L and the driven wheel 60R) are provided so as to support the leftpart 41 b and the right part 41 c of the riding part 40. However, adriven wheel can be provided in other parts. For example, a singledriven wheel can be provided below the central part 41 a of the ridingpart 40, or a driven wheel can be provided in the rear part of themachine body frame 11 (lower frame 11 a). That is, the driven wheel canbe disposed at an arbitrary position different from the a rotationalaxis of the driving wheel 30L and the driving wheel 30R so as to supportthe traveling vehicle 1. Additionally, the number of driven wheels isnot limited, any number of driving wheels may be provided.

In each of the above embodiments, the mower unit 90 is exemplified as awork device. However, another work device (e.g., a snow removing deviceor the like) can be used.

In each of the above embodiments, the rotation angle sensor (such as therotation angle sensor 80) is configured by a potentiometer. However, anyother sensor capable of detecting a rotation angle (such as a rotaryencoder and a gyro sensor) can be used.

In each of the above embodiments, the traveling vehicle 1 is drivenbased on the weight shift of a worker and the swinging operation of thehandle 70. However, the disclosure is not limited to this. For example,the handle 70 can be provided with an operation tool such as a joystick,and configured to drive the traveling vehicle 1 based on the weightshift of a worker and the operation of the operation tool.

The handle 70 described in each of the above embodiments is an example,and the shape or the like (e.g., the shape, or the position, or the likeof the grip part 73) can be optionally changed. At this time, the heightof the fulcrum shaft 71 that serves as a swing fulcrum of the handle 70preferably is set to a range from at most a half of the height of thegrip part 73 from the leg placing surfaces to at least one-third of theheight of the grip part 73.

The number or the arrangement of the load sensors described in each ofthe above embodiments is an example, and is not limited. For example, itis possible to improve the detection accuracy of the weight shift of aworker by increasing the number of load sensors, or to prevent themalfunction of the traveling vehicle 1 when any of the load sensors isbroken.

The arrangement of each member of the motive power part 20 described ineach of the above embodiments is an example. As many members as possibleare disposed at such a position as to overlap with the driving wheel 30Land the driving wheel 30R in side view, so that the traveling machinebody 10 can be made compact.

The invention claimed is:
 1. A traveling vehicle comprising: a travelingmachine body supported by a pair of left and right driving wheels; apair of left and right motors connected to the pair of left and rightdriving wheels, respectively, and configured to independently drive thepair of left and right driving wheels, respectively; a riding partdisposed behind the traveling machine body, connected to the travelingmachine body, configured to enable riding of a worker, and including aleg placing surface on which the worker places his/her leg when riding;a handle formed with a grip part configured to enable gripping by theworker who is riding on the riding part, the handle being connected tothe traveling machine body so as to be swingable left and right about aswing fulcrum with respect to the traveling machine body, and providedat such a position that a height of the swing fulcrum is at most a halfof a height from the leg placing surface to the grip part, and is higherthan a height of the leg placing surface; a swinging operation detectionsensor configured to detect a leftward and rightward swinging operationamount of the handle; and a controller configured to control operationof the pair of left and right motors based on a detection value by theswinging operation detection sensor.
 2. The traveling vehicle as claimedin claim 1, further comprising: a motive power part for generating powerfor driving the pair of left and right driving wheels and transmittingthe power to the pair of left and right driving wheels, the motive powerpart being provided in the traveling machine body; the motive power partbeing disposed below the swing fulcrum.
 3. The traveling vehicle asclaimed in claim 1, further comprising: a motive power part forgenerating power for driving the pair of left and right driving wheelsand transmitting the power to the pair of left and right driving wheels,the motive power part being provided in the traveling machine body; themotive power part including at least one of the motors, the controller,and a battery for supplying electric power to the motors.
 4. Thetraveling vehicle as claimed in claim 1, wherein: the swing fulcrum isprovided at a height that is at least one-third of a height from the legplacing surface to the grip part.
 5. A traveling vehicle comprising: atraveling machine body supported by a pair of left and right drivingwheels; a pair of left and right motors connected to the pair of leftand right driving wheels, respectively, and configured to independentlydrive the pair of left and right driving wheels, respectively; a workdevice disposed in front of the traveling machine body, and connected tothe traveling machine body; a riding part disposed behind the travelingmachine body, connected to the traveling machine body, and configured toenable riding of a worker; a handle connected to the traveling machinebody so as to be swingable left and right with respect to the travelingmachine body; a weight shift detection sensor configured to detect aforward and backward weight shift of the worker who is riding on theriding part; a swinging operation detection sensor configured to detecta leftward and rightward swinging operation amount of the handle; and acontroller configured to control operation of the pair of left and rightmotors based on detection values by the weight shift detection sensorand the swinging operation detection sensor.
 6. The traveling vehicle asclaimed in claim 5, wherein: the weight shift detection sensor includesa plurality of load sensors disposed by being shifted in a front andback direction.
 7. The traveling vehicle as claimed in claim 5, wherein:the riding part includes a first member connected to the travelingmachine body, and a second member disposed above the first member, andformed with a leg placing surface on which the worker rides; and theweight shift detection sensor is provided between the first member andthe second member.
 8. The traveling vehicle as claimed in claim 5,wherein: the swinging operation detection sensor includes a rotationangle sensor configured to detect a leftward and rightward swing angleof the handle.
 9. The traveling vehicle as claimed in claim 1, wherein:the swing fulcrum extends in a front-and-back direction.
 10. Thetraveling vehicle as claimed in claim 9, wherein: the swing fulcrumcomprises a front-and-back extending shaft.
 11. The traveling vehicle asclaimed in claim 1, wherein: the leg placing surface is spaced upwardlyfrom a ground surface on which the traveling machine is supported duringsaid riding of a worker.